SYDNEY, Australia — A video game that uses footage of the Christchurch massacre to put Muslims in a gunman’s cross hairs. Memes featuring the face and weapons of the man charged in that New Zealand attack. Messages on online forums that glorify him as St. Tarrant — patron saint of the far right.

New Zealand has worked hard to keep the name of Brenton Tarrant, the man charged with killing 51 Muslims in Christchurch, out of the news, and to restrict the spread online of the hateful ideology he is accused of promoting. But the footage, games, memes and messages that still populate the dark corners of the global internet underline the immensity of the task, especially for a small country like New Zealand.

“The internet is a very complex and rough environment, and governments, especially small governments, don’t have as many cards as they would like to play,” said Ben Buchanan, a cybersecurity expert who teaches at Georgetown University.

Read the full article in The New York Times.